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arXiv · 2501.11964

Harnessing Chiral Spin States in Molecular Nanomagnets for Quantum Technologies

Aman Ullah·Ziqi Hu·Juan Aragó·Alejandro Gaita-Ariño
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Abstract

We present a theoretical framework to investigate spin chirality in molecular quantum systems. Focusing on a minimal three-spin-center model with antiferromagnetic exchange and symmetry breaking driven by an electric-field-induced Dzyaloshinskii-Moriya interaction and applied magnetic fields-give rise to chiral ground states characterized by nonzero scalar spin chirality, $\chi = \textbf{S}_1\cdot(\textbf{S}_r\times \textbf{S}_2)$. The emergent chiral qubits naturally suppress always-on interactions that can not be switched off in weakly coupled qubits, as demonstrated through Liouville-von Neumann dynamics, which reveal phase difference in superposition states that form chiral qubits. To validate this framework, we examine realistic lanthanide complexes with radical-bridged magnetic centers, where spin-orbit coupling and asymmetric exchange facilitate chirality. Our findings establish spin chirality engineering as a promising strategy for mitigating always-on interaction in entangling two chiral qubits in molecular quantum technologies.

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Aman Ullah, Ziqi Hu, Juan Aragó, Alejandro Gaita-Ariño. 2025-01-21. Harnessing Chiral Spin States in Molecular Nanomagnets for Quantum Technologies. https://arxiv.org/abs/2501.11964

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